(a) Field of the Invention
The present invention relates to an improved structure of a floating-ball valve, in particular, to a floating-ball valve to be used in various type of water tank or water trough to automatically control water entrance to the tank or water level. This valve is particularly suitable to water tank for the high temperature steam producer or humidifier.
(b) Description of the Prior Art
ROC publication no. 31 9396 discloses a conventional floating-ball valve structure, as shown in FIGS. 1 to 4, comprising a valve seat 1, a valve insert 2, and an arm rod 31. The valve seat 1 is a pipe body with various internal diameters. A water passage is provided to the pipe body and a row of water-discharge holes 12 are provided within the large internal diameter of the pipe body. The pipe body per se is provided with a protruded member 13 and the valve insert 2 is a cylindrical mounting body mounted within the valve seat 1, and the external end of the arm rod 31 is connected to a floating-ball 5. The characteristics of the inventions are that: the water passage is provided with a conic face 10 (refer to FIG. 4), and the top end of the valve insert 2 has a mounting connection 21 of smaller external diameter, and the external diameter of the mounting connection 21 is larger than the small internal diameter of the valve body 1, and the front end of the mounting connection 21 has a conic face 211, which corresponds to the conic face 10 of the valve chamber 1, thereby, when the valve insert 2 is pushed towards the valve body 1 from the rear end thereof to the conic face 1, a closer seal is formed and the water passage of the valve body is thus blocked.
As the conic faces 10, 211 are metallic faces, their function as water blockage is not effective, and the mounting connection 21 of the surface of the conic face 211 will adsorb metallic debris after long period of water stream impact, and the function of water blockage for the conic surfaces is greatly reduced. In addition, the end opening of the valve insert 2 is not sealed and there is a small gap in between the valve seat 1 and the valve insert 2. Therefore, when water flows via the water inlet of the valve seat 1, a portion of the water stream will eject out from the end opening of the valve seat 1. If the valve is used on a stem producing apparatus, humidifier, or/and humidifying device, then, the discharged water stream (or steam) mixed with high temperature steam will be discharged via a transporting pipe. Thus, the steam contained chilled water is re-directed to the room, as a result, the chilled water is not vaporized but the humidity of the room is increased. Thus, the conventional floating-ball valve is not suitable to be used in all industrial purposes. Further, during water entering the valve seat 1, the movement of the valve insert 2 only provides half opening of the discharge hole 12 (being unable of fully opened), and the speed of water stream is too slow, which causes the water stream to eject out from the end opening of the valve seat 1. Thus, the moving distance of the valve insert 2 and the structure of the valve insert 2 have to be improved in order to provide normal water discharge.